Turkish President Recep Tayyip Erdogan’s ambitions to concentrate powers in his office depend on formal talks that were to begin Monday between the ruling AK Party and a nationalist opposition party, which is leaning toward referring the controversial issue to a popular referendum.

Secretary General Abdulhamit Gul of AKP and lawmaker Mehmet Parsak of the opposition Nationalist Movement Party, or MHP, were expected to meet Monday to discuss the ruling party’s proposal to introduce an executive presidency through a constitutional amendment, according to Parsak’s office.

Erdogan stepped up his push for a presidential system following the failed coup attempt in July, arguing that the military takeover plot proved the nation would be more stable if ruled from the presidential palace. His call to reinstate the death penalty was quickly endorsed by MHP leader Devlet Bahceli, whose backing is crucial for AKP to win the 330 votes needed in the 550-seat parliament to bring a referendum on the presidential system to the public. Bahceli has said AKP’s proposals on the new constitution were “positive and reasonable.”

The lira slid more than 17 percent against the dollar since the July 15 coup attempt as the government purged more than 110,000 people from the civil service, seized hundreds of businesses and shut down more than a dozen media outlets suspected of ties to the cleric the government accuses of masterminding the coup attempt. The preacher, U.S.-based Islamic cleric Fethullah Gulen, denies any involvement.